Collapsible heating pad for travelling



April 21, 1964 L.. KATzMAN ETAL COLLAPSIBLEHEATING PAD FOR TRAVELLING Filed oct. 12, 1962 United States Patent O M 3,130,289 COLLAPSIBLE HEATING PAD FOR TRAVELLING Lawrence Katzrnan and Robert Dublirer, New York, NKY., assignors to Kaz Heating Products, Inc., New York, N.Y., a corporation of New York Filed Get. 12, 1962, Ser. No. 230,086 1 Claim. (Cl. 219-46) This invention relates to the class of heating devices and more particularly to a collapsible heating pad for use when travelling.

In the past, conventional heating pads have been used by travellers on aircraft, ships, trains, buses, automobiles and other forms of transportation, and in foreign lands to obtain the usual comfort and therapeutic eiect provided by such devices. However, because of the construction of most conventional heating pads wherein the heating coils are sewn to the backing material, and because of the fact that the heating coils are formed of relatively nonflexible material such as copper, copper alloys, aluminum or the like, conventional heating pads are rather bulky and cannot be folded or otherwise compressed into a small area for storage or packing when travelling. Further, if conventional heating pads are tightly folded, the'heating coils are bent and are often distorted or broken rendering the heating pad inoperative. In addition, heating pads in the past have been designed for operation either for ll() to 220 volts or for 120 to 240 volts depending upon the usual source of supply and are not adapted for operation at both of these ranges of voltages. Since in different countries, the commercially supplied electrical power is at varying voltages dependent upon the country, primarily ranging in the order of l1() volts or in the order of 220 volts, heating pads of conventional construction have been unsatisfactory for use when travelling since the use of beatings designed for 110 volt voltage will cause the pads to be burned out while heating pads designed for 220 volts will not heat up satisfactorily when supplied with 110 volt current.

The present invention has as its primary object the provision of a heating pad designed especially for travelling and designed to be collapsed into a very small compass for carrying and packing while also being capable of being used for either 110 volt or 22() volt supply without the possibility of burning out the coils of the heating ad. p A further object of the present invention resides in the provision ot a heating pad that is provided with means for eliminating deleterious effects upon radios, television sets, and other electronic equipment while the heating pad is in use.

An yadditional object of the invention resides in the provision of a collapsible heating pad for travelling that is designed to be used with conventional 6 volt or 12 volt automobile electrical supply circuits.

In accordance with the concepts of the present invention, a novel switch arrangement is provided wherein a switch has successively an off position, a 220-240 Volt position, a 110-120 Volt position and a 6-12 volt position for selectively connecting one of a number of heating coils in series with an electrical cord for connection to a source of electrical power.

-In accordance with an illustrative embodiment of the present invention there is provided a collapsible heating pad for travelling which comprises at least two insulated heating coils arranged in 'abutting relationship between a pair of denim sheets. The heating coils are sandwiched between and bonded to the denim sheets and the denim sheets are bonded to each other. These denim sheets are extremely flexible and securely encompass the heating coils, preventing shifting of the heating coils relative to 3,130,289 Patented Apr. 21, 1964 the denim while permitting the collapsing or bending of the heating coils and the denim sheets without requiring the sewing or stitching of the coils to the denim sheet which would render the heating pad less llexible. Cotton linettes are bonded to the denim sheets with an envelope of rubber sheeting surrounding the cotton linettes. There is provided a removable casing of decorative fabric for covering the envelope so that the entire collapsible heating pad may have an attractive exterior and may be soft and comfortable to the user. A conductor having at least three lines is connected to the heating coils and a multiple position switch is connected to the conductor with a two-line cord being connected to the switch for connection to a source of electrical power. The switch is a multiple position switch which selectively connects one of the heating coils in series with the cord and is designed so that during normal use, the entire heating pad is protected against being burned out.

Still further objects and features of this invention reside in the provision of a collapsible heating pad for travelling that is simple in construction, capable of being manufactured by mass production methods and at relatively low cost so as to permit wide use and distribution, and which is safe and easy to use.

These, together with the various ancillary objects and features of the invention which will become apparent as the following description proceeds, are attained by this collapsible heating pad for travelling, preferred embodiments of which have been illustrated in the accompanying drawings, by way of example only, wherein:

FIG. 1 is a plan view of an embodiment of the collapsible heating pad for travelling with parts thereof being broken away to illustrate other parts in detail;

FIG. 2 is a wiring diagram of the electrical components of this collapsible heating pad;

FIG. 3 is a sectional detail view taken along the plane of line 3 3 in FIG. 1, illustrating in an enlarged scale the construction of the various components of this invention;

FIG. 4 is an elevational view showing the manner in which an adapter is provided for connection to the plug of the two-line cord for adapting the device for use with either or 220 volt electrical supply;

FIG. 5 is a view similar to FIG. 3 illustrating a modied form of the invention adapted not only for use with 1l() and 220 volt supply but also for use with 6l2 volt Supply;

FIG. 6 is a circuit diagram of the electrical components of the embodiment of the invention shown in FIG. 5;

FIG. 7 is an elevational view illustrating the adapters which may be alternately used in connection with the electrical cord for connection to the source of electrical Vpower supply; and

FIG. 8 is an enlarged sectional view taken along the plane of line 8-8 in FIG. 5 illustrating the various constructional elements used in the invention.

With continuing reference to the accompanying drawings wherein like reference numerals designate similar parts throughout the various views, reference numeral 10 generally designate an embodiment of the collapsible heating pad designed for use when travelling in accordance with the concepts of the present invention. This heating pad includes a pair of heating coils 12 and 14 which are formed of copper or a copper alloy and are wrapped with asbestos or like material, thereby electrically insulating the heating coils from each other while also provided an enlarged surface for disseminating heat from the coils. The heating coils 12 and 14 are arranged in abutting relationship and are disposed in a substantially sinusoidal path to cover the entire area of the heating pad.

There is provided a pair of sheets of denim material 16 and i8 which have the heating coils 12 and 14 sandwiched therebetween. The heating coils l2 and 14 are bonded to the denim sheets and the denim sheets 16 and 1S are bonded to each other. Disposed between the denim sheets and bonded to the denim sheets are a capacitor 2li and a pair of thermally responsive switches or thermostats 22 and 24. Electrically connected to the heating coils l2 and f4 and secured to the denim sheets and having an end bonded between the denim sheets is a conductor Z6 having three lines 2S, 3b, and 32. The line 30 is electrically connected to the thermally responsive switches 22 and 24- which are disposed along different portions of the heating pad lil so as to control the temperature thereof and the capacitor 2% is connected in parallel with the thermally responsive switches 22 and 24 as can be seen best in FIG. 2.

Cotton linettes 34 and 35 overlie and are bonded to the denim sheets lo and lb, the cotton linettes being in the form of cotton material having soft, resilient and flexible cotton fibers. An envelope of rubber sheeting 38 surrounds the cotton linettes and provides a waterproof, substantially air-proof, and electrically insulating protective covering for the collapsible heating pad. A removable casing 4b of a decorated fabric material is provided for covering the envelope.

A multiple-position switch 44 is connected to the conductor 2.6 and a two-line cord 4o is connected to the switch 44 for connection through plug 4S to a source of electrical power.

As can be seen in FIG. 2, the switch 44 is of a threeposition type, having an olf position 50, a 220-240 volt position 52 and a 11C-120 volt position 54.

When the switch is in the olf position, there is an open circuit to the heating coils l2 and i4.' Vhen the switch is in the position S2, the heating coil 12 is connected electrically to the source of electrical power. Thus, the 220 volt heating coil is supplied with electrical power. If the plug 43 is connected to a 110 volt power supply, unless the coil l2 has been pre-heated, it will not conduct sufficient current to heat the coil. An adapter 65E is provided for connection to the plug 43 so that the cord 46 may be connected to a conventional source of 220-240 volt power, the plug being shown in FIG. 4. With the cord 46 connected to a source of 22S-240 volt power supply, the coil l2 will heat sulliciently to provide a maximum amount of suitable heat to the user. The temperature is controlled by means of the thermally responsive switches 22 and 24 which will open, breaking the circuit from the power supply through the heating coil 12 when the temperature goes above a certain predetermined and preset limit. The condenser 2t] prevents any sparking of the switches 22 and 24 from adversely affecting nearby electronic devices such as television sets, radios or the like which may be in use when travelling. For example, the heating pad can be utilized even in airplanes or the like without adversely affecting the electronic equipment aboard because of the use of the capacitor 20.

The switch 44 is thrown to the position S4 when the cord 46 is connected to a source of 110 volt power. If the switch is in the position 52 when the cord 46 is connected to a source of 110 volt and the 220 volt coil 12 has been preheated by use of the heating pad with 110 volts and through operation of the coil 14- to fully heat the pad, the coil 12 will then be useful as a reduced heat source and will be operative. However, should the heating pad not have been preheated, the heating coil 12 will not operate. This is a quite unexpected result achieved from the use of the coils l2 and i4 arranged in abutting relationship.

It is noted that the heating coil 14 is of suliicient resistance to prevent being burned out if inadvertently the switch 44 is turned to the 11G-120 volt position S4 while the plug 46 is connected to a 220-240 volt supply. However, in such case the thermally responsive switches 22 and 24 will soon open due to the fact that the coil i4 will heat to the required temperature for operation of switches 22 and 24 thus preventing early accidental burn out. However, it is to be noted that one of the features of the invention is that the switch 44 is arranged so that when the heating pad is properly connected to a 22S-240 volt supply, and the switch is in position 52, it is not necessary to pass the switch through the setting for llo-120 volts when moving the switch to its olf position Sil, nor is it necessary to move through the 11G-l2() volt position 54 when moving the "220 volt position 52. This is a further safeguard for the invention.

As shown in the embodiment of FIGS. 5 through 8, the invention is adapted to be used with a 6 or 12 volt supply such as provided in the conventional automobile electrical system. An adapter 7@ is provided which can be connected to an automobile cigarette lighter, the adapter 7l) being designed to tit over and be connected to the plug 4S such as is used in the embodiment of FIGS. l through 4. Thus, in addition to the other elements of the invention which are used in the embodiment of FlG. 4, a further heating coil 72 is arranged in abutting relationship to the coil l2 and i4' similar to the coils l2 and 14. The heating pad is assembled in much the same manner and a condenser Ztl is connected in parallel with thermally responsive switches ZZ and 24. he heating coils are sandwiched between layers of denim lli and lli. Cotton linettes 54 and 36 are bonded to the sheets of denim i6 and l and an envelope 38' of rubber material completely surrounds and provides a waterproof insulative enclosure for the heating pad. A removable and washable casing of decorator fabric 40 covers the envelope 33'.

A conductor 26', having four lines, is connected to the heating coils l2', 14 and 72 and to the respective thermally responsive switches 22', 24 and the condenser 2lb.

The four line conductor 26' is connected to a four-way switch 44', similar in operation to the switch 44, but with the difference that the switch 44' includes positions Sil', 52', 54 and a further position 53. It is noted that the 6-12 volt position 55 is not passed through when the switch is moved from its olf position Sti to either the positions S2 or 54, thus safeguarding the operation of the mechanism and the 6-12 volt heating coils against deterioration due to malposition of the switch 44.

In operation, the abutting relationship of the heating coils serves to permit the volt heating coil to heat the pad to a sufficient degree so as to render the 220 volt heating coil conductive so as to conduct a limited amount of current and to develop heat through its resistance whereby the 220 volt heating coil will serve as a low-heat position in the normal 110-120 volt supply circuit arrangement.

Thus, it can be seen that there has been provided a collapsible heating pad especially adapted for travel wherein the heating pad can be used with substantially all of the normal electrical supply circuits in each foreign country. Most foreign countries utilize commercial electrical supply circuits, either in the range of 1l0-l20 volts or in the range 1220-240 volts and this heating pad can accommodate supply circuits which are of either range or close thereto.

Further, the embodiment as shown in FIGS. 4 through 8 can be used with the conventional distribution system of an automobile.

A latitude of modification, change and substitution is intended in the foregoing disclosure, and in some instances, some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claim be construed broadly and in a manner consistent with the spirit and scope of the invention herein.

We claim:

A collapsible heating pad for travelling comprising a first heating coil for connection to a 220-240 volt supply, a second heating coil for connection to a 11G-120 volt supply, said rst heating coil being in abutting relationship With said second heating coil for preheating thereby, said first and second coils being arranged in a sinusoidal pattern, a pair of sheets of denim, said heating coils being sandwiched between and bonded to said denim sheets, said denim sheets being bonded to each other, cotton linettes overlying and bonded to said denim sheets, an envelope of rubber sheeting surrounding said cotton linettes, a removable casing of decorated fabric covering said envelope, said heating pad being foldable and bendable in all directions, a conductor having at least three lines connected to said heating coils, a multiple position switch connected to said conductor, a two line cord connected to said switch and for connection to a source of electrical power, said switch having successively an 01T position, a 220-240 volt position and a 110-120 volt position, and selectively connecting the corresponding one of said heating coils in series with said cord when in said 220-240 volt position and said 110-120 Volt position, a pair of spaced thermal responsive switches disposed between said sheets of denim and bonded thereto and connected in series connection with said cord, and a condenser bonded to said denim sheets and disposed therebetween, said condenser being connected in parallel with said thermal responsive switches.

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